On April 30, climbing lost one of its greats, Ueli Steck, in a fall on Nuptse, in the Khumbu Himalayas of Nepal. Ueli was alone, acclimating on the mountain at night, when one of the millions of crampon placements he made over his lifetime gave way, and he fell 3,000 feet to his death. We will never know the exact circumstances, but too often it is the simple mistake that catches us unaware.

Ueli had his sights set on a route up Everest’s notorious West Ridge, one that was first climbed in 1963 but has not been repeated since, despite numerous attempts. (I tried it with a team in 2012 but called off the climb due to poor snow conditions high on the mountain.) After topping out on Everest, Ueli had planned to traverse directly to the summit of 27,940-foot Lhotse, without coming down from elevation.

Had he been successful, it would have been the ultimate test in human endurance at altitude — an exposed traverse over technical ground during an almost nonstop, four-day push. Doing it without supplemental oxygen, as Ueli had planned, elevated the stakes considerably. Few climbers, myself included, would fully consider such a thing. This was typical Ueli.

Ueli and I never roped up together in the mountains, but our paths crossed often. In 2005, I was leading a team up the southwest ridge of Cholatse, in Nepal, when we encountered a lone set of tracks weaving through the icefall. These transient footsteps, frozen briefly in time, were from Ueli after a solo ascent of the imposing north face. My team and I nodded in respect, yet we also asked ourselves, “Would we accept the risk of climbing through an active, constantly shifting icefall?”

In 2012, during my attempt at Everest’s West Ridge, Ueli and I shared base camp. Ueli was on the mountain for an ascent of the South Col route without supplemental oxygen. We would meet up for tea, do a snap evaluation of the teams on the mountain, and laugh at our shared obsession with the details. We both kept meticulous diaries, noting weather, personal health, a list of radio frequencies, and the expenses of our expeditions. Over the years, we would also run into each other at film festivals and trade shows. As professional climbers, we followed the same seasons and were motivated by the same forces. Climbing was our life.

Ueli grew up in the shadow of the Eiger, in Switzerland, a mountain that came to define him. He first climbed it at 18, and he would ultimately transform the time needed to ascend the standard route, setting the speed record three times. His final time, at two hours and 22 minutes — this on a peak that can take days for many mountaineers — still holds. Ueli did it by running up the ice fields and moving over technical terrain with no protection. To achieve this required dedication to training, for both aerobic capacity and psychological preparedness, and it was his ability to move fast and light on exposed terrain that set him apart. It also helped revolutionize the sport. (Once, in response to carrying too much food in the mountains, he said, “We are going climbing, not going out for a picnic.”) Ueli’s speed dominance on the Eiger, paired with his home country’s identity for all things mechanical, led to his nickname, the Swiss Machine. He was never fond of it, yet it became part and parcel of the public figure he had become on account of his stunning successes in the mountains.

Steck during an acclimation climb in the Himalayas in 2016.Patitucci Photo

With the Alps as a springboard, Ueli set his sights on the Himalayas, and in 2013 he set off to tackle the elusive West Ridge of Everest. The climb was cut short due to a well-publicized altercation with the Sherpa crews working on the mountain, who were upset that Ueli and his team were climbing above them as they fixed ropes lower on the mountain. After the confrontation, Ueli abandoned his climb and left the country. The media cast him as something of a villain in the wake of the incident, and Ueli was deeply affected by this portrayal. He genuinely cared for the people of Nepal, even if he didn’t like what Everest, with its crowds, had become. Many of his climbing partners were Nepalese, including his partner this season, Tenji Sherpa, a young man with incredible strength.

In 2013, Ueli found a degree of redemption in his solo ascent of the south face of Annapurna, a peak he had tried twice before. It entailed climbing and descending one of the tallest and most complex faces in the Himalayas in an astonishing 28 hours. The south face climb was a generation ahead of its time, and the feat earned Ueli his second Piolet d’Or, climbing’s highest honor. It also established Ueli as the leading climber of his era: From hard sport climbs to mixed ice and rock routes, Ueli excelled at the game of gravity in all mediums.

Falls and avalanches are the foremost causes of death in the Himalayas, and as alpinists, we often mull over the moment between incident and the finality of death. A fall like Ueli’s is instant, accelerating past the chance to self-arrest until the mind blacks out. Being buried in an avalanche, as I have and survived, is merciless. With minutes before asphyxiation takes hold, one has a chance to reflect on what went wrong and the impact your passing will have on your family. In this way, high-stakes alpinism is a selfish game. The practitioners reap the rewards; family and friends pay the price. Having played both ends of the spectrum — more often from the selfish aspect — I know that loss is a very real issue that alpinists have to deal with. It is never easy.

As a climber, I’m often reminded of an Albert Camus quote: “Whether or not one can live with one’s passions, whether or not one can accept their law, which is to burn the heart they simultaneously exalt, that is the whole question.” No sport more fully embodies this insight into mortality than solo speed climbing in the Himalayas. As a proponent of fast and light climbing, Ueli was well aware of its unforgiving nature. In climbing there are no second chances.

Yet this is what we live for. In an update from base camp this spring, Ueli wrote, “Mountaineering is a transient experience. I need to continuously repeat it to live it.” Ueli lived to climb, and his singular focus allowed him to take his body and mental game to places even the best of us, including me, can only imagine.

Ueli, we miss you and are reminded of you with the words you shared with us in April as you set out for this adventure: “And now I’ll just go, and only worry about the events that lie ahead of me. Day by day, one by one. It is the here and now that counts. What comes next is uncertain in any case. Learn from yesterday, live for today, hope for tomorrow.”